Calibration of a chemical dispense system

ABSTRACT

Method for providing a fluid at a target pressure. In one implementation, the method may include providing a semiconductor solution at a velocity to a supply line through a dispenser, measuring a pressure of the semiconductor solution flowing through the supply line, comparing the measured pressure with the target pressure, and adjusting the velocity based on the results of the comparison.

GOVERNMENT RIGHTS IN THIS INVENTION

This invention was made with U.S. government support under contractnumber H94003-07-C-0712. The U.S. government has certain rights in thisinvention.

BACKGROUND

1. Field of the Invention

Implementations of various technologies described herein generallyrelate to substrate processing.

2. Description of the Related Art

The following descriptions and examples do not constitute an admissionas prior art by virtue of their inclusion within this section.

To achieve the desired performance enhancement for each successivegeneration of silicon integrated circuits (ICs), semiconductormanufacturing has become increasingly reliant on new materials and theirintegration into advanced process sequences. Unfortunately, typicalsemiconductor manufacturing equipment is not well suited for materialsexploration and integration. Issues impacting the use of typicalsemiconductor manufacturing equipment include difficulty in changingprocess materials and chemicals rapidly, limited ability to integrateand sequence multiple materials or chemicals in a single reactor orprocess chamber, high equipment cost, large sample size (e.g. 300 mmwafers) and inflexible process/reactor configurations. To complementtraditional manufacturing tools, a need has arisen for process equipmentthat facilitates fast testing of new materials and materials processingsequences over a wide range of process conditions.

BRIEF DESCRIPTION OF THE DRAWINGS

Implementations of various technologies will hereafter be described withreference to the accompanying drawings. It should be understood,however, that the accompanying drawings illustrate only the variousimplementations described herein and are not meant to limit the scope ofvarious technologies described herein.

FIG. 1A illustrates a schematic diagram for implementing combinatorialprocessing in connection with implementations of various technologiesdescribed herein.

FIG. 1B illustrates an exemplary substrate containing multiple regionsfor combinatorial processing according to implementations of varioustechnologies described herein.

FIG. 2 illustrates a combinatorial processing tool in which varioustechnologies may be incorporated and used in accordance with varioustechniques described herein.

FIG. 3 illustrates a schematic diagram of a combinatorial processingtool according to implementations of various techniques describedherein.

FIG. 4 illustrates a flow diagram of a method for calibrating a chemicaldispense system according to implementations of various techniquesdescribed herein.

FIG. 5 illustrates a flow diagram of a method for providing a chemicaldispense system with a predetermined volume of a fluid according toimplementations of various techniques described herein.

FIG. 6 illustrates a flow diagram of a method for providing a fluid to achemical dispense system at a predetermined pressure according toimplementations of various techniques described herein.

DETAILED DESCRIPTION

The following paragraphs provide a brief general description of one ormore implementations of various technologies and techniques directed atcalibrating a fluid flow rate with respect to a pressure in a chemicaldispense system that may be part of a combinatorial processing tool. Inone implementation, the fluid may be a liquid chemical used in thecombinatorial processing tool. A dispenser, such as a syringe,containing the fluid may be coupled to a supply line of the chemicaldispense system. The supply line may be coupled to a supply manifoldhaving a plurality of valves. Each valve may be coupled to a dispenseline, which may be used to provide the fluid a path to one or morevessels and/or one or more reactors within the combinatorial processingtool. A pressure indicator may be coupled to the supply line to measurethe pressure available at the supply line.

A controller may be coupled to a motor, which may be configured to pusha plunger of the dispenser. In one implementation, the motor may pushthe plunger at a constant velocity or at a velocity with a constantacceleration such that the fluid contained within the dispenser may beprovided to the supply line with a constant flow rate or a flow ratewith a constant acceleration. The resulting pressure at the supply linemay then be measured by the pressure indicator. Given the volume offluid dispensed into the supply line by the dispenser and the timeelapsed in providing the volume of fluid, the controller may determinethe flow rate of the fluid provided to the supply line. The flow rate ofthe fluid may then be recorded along with a corresponding pressure valueobtained from the pressure indicator. The resulting fluid flow rate andpressure data may then be used as calibration data that may correlate afluid flow rate to its pressure value.

In another implementation, the controller may use the calibration datathat correlates a fluid's flow rate to its pressure value to provide aspecified volume of a fluid into a destination vessel. The controllermay first receive inputs from a user specifying a target pressure and aspecific volume of the fluid to be provided to the destination vessel.The controller may then determine the fluid flow rate that correspondswith the fluid and the specified target pressure from the calibrationdata of the chemical dispensing system. Using the fluid flow rate, thecontroller may calculate an amount of time required to fill thedestination vessel with the specified volume of the fluid at the targetpressure. The controller may then allow the fluid to flow to thedestination vessel at the target pressure for the calculated amount oftime. The resulting volume of fluid in the destination vessel may beequal to the volume originally specified by the user.

In yet another implementation, the controller may also be used toprovide a fluid to the supply line at a specified pressure. Afterreceiving a specific pressure value from a user, the controller may senda command to the motor to push the plunger at a constant velocity. Apressure indicator may be used to measure the corresponding pressure ofthe fluid being provided into the supply line. The controller mayreceive the corresponding pressure value from the pressure indicator,and it may compare this received pressure value with the pressure valuespecified by the user. Based on the results of the comparison, thecontroller may increase or decrease the velocity in which the motorpushes the plunger in the dispenser in order to provide the fluid at theuser's specified pressure value.

The various implementations in calibrating a chemical dispense systemwith a dispenser may have advantages in that they may ensure that achemical may be delivered to one or more vessels or reactors in acombinatorial process tool at a specified flow rate, volume, orpressure. The ability to specify the flow rate, volume, or pressure mayincrease the accuracy in which a chemical reaction takes place for acombinatorial process. Furthermore, the use of a dispenser may eliminatethe need for a flow meter, which may consequently reduce the complexityand costs while increasing the accuracy of the combinatorial processingtool. The dispenser may be used to accurately dispense a small amount ofa chemical while measuring the flow rate of the chemical which may alsobe useful for combinatorial processing. The dispenser may also be usedto determine the flow rate properties or calibration data of thechemical dispense system and its various dispense paths. The calibrationdata may improve the consistency and repeatability of the combinatorialprocess by accurately measuring the flow rate for each dispense pathconnected to a vessel or a reactor.

One or more implementations of various techniques for calibrating achemical dispense system with a dispenser will now be described in moredetail with reference to FIGS. 1-5 in the following paragraphs.

The discussion below is directed to certain implementations. It is to beunderstood that the discussion below is only for the purpose of enablinga person with ordinary skill in the art to make and use any subjectmatter defined now or later by the patent “claims” found in any issuedpatent herein.

Combinatorial processing may include any processing, includingsemiconductor processing, which varies the processing conditions acrossone or more substrates. As used herein, a substrate may be, for example,a semiconductor wafer, a portion of a semiconductor wafer, solarphotovoltaic circuitry, or other semiconductor substrate. The term“substrate” includes a coupon, which is a diced portion of a wafer, orany other device on which semiconductor processes are performed. Thecoupon or substrate may optionally contain one die, multiple dice(connected or not through the scribe), or portion of die with useabletest structures. In some implementations, multiple coupons, or die canbe diced from a single wafer and processed combinatorially.

Combinatorial processing is performed by varying processing conditionsacross multiple substrates, multiple regions of a single substrate, or acombination of the two. Processing conditions may include, for example,chemical formulation, fluid flow rates, temperatures, reaction times,concentrations, agitation or stirring, and the like. For example, afirst region of a substrate may be processed using a first processcondition (e.g., applying a chemical at a first temperature) and asecond region of the substrate may be processed using a second processcondition (e.g., applying the chemical at a second temperature). Theresults (e.g., the measured characteristics of the processed regions)are evaluated, and none, one, or both of the process conditions may beselected as suitable candidates for larger scale processing (e.g.,further combinatorial processing or deposition on a full wafer).

Several combinatorial processing tools can be used. One type of tool mayinclude a reactor block that has several openings (e.g., cylindricalopenings) that define individual reactors on one or more substrates.Each of the openings may further include a sleeve that creates a sealwith the substrate to contain processing fluids or chemicals within asingle reactor (i.e., “site-isolated”). For example, a reactor block mayinclude 28 openings that define 28 regions on a substrate. Each of the28 regions can be processed using varying process conditions, ormultiple regions can have the same processing conditions. For example,seven sets of processing conditions can be performed across four regionseach. Each region can then be characterized using various techniques(e.g., electrical test, microscopy), and useful or beneficial techniquesand/or conditions can be selected.

Other combinatorial processing may be performed in a manner that is notsite isolated. For example, a wafer can be divided into many smallcoupons, each of which can be processed using different conditions.Using another example, a wafer can be processed using a gradientapproach, where the processing varies over the substrate. Thesetechniques may also be used in combination with site-isolatedcombinatorial techniques.

FIG. 1A illustrates a schematic diagram 100 for implementingcombinatorial processing in connection with implementations of one ormore technologies described herein. The schematic diagram 100illustrates that the relative number of combinatorial processes that runwith a group of substrates decreases as certain materials and/orprocesses are selected. Generally, combinatorial processing includesperforming a large number of processes during a first screen, selectingpromising candidates from those processes, performing the selectedprocessing during a second screen, selecting promising candidates fromthe second screen, and so on. In addition, feedback from later stages toearlier stages can be used to refine the success criteria and providebetter screening results.

For example, thousands of materials are evaluated during a materialsdiscovery stage 102. Materials discovery stage 102 is also known as aprimary screening stage performed using primary screening techniques.Primary screening techniques may include dividing wafers into couponsand depositing materials using varied processes. The materials are thenevaluated, and promising candidates are advanced to the secondaryscreen, i.e., materials and process development stage 104. Evaluation ofthe materials may be performed using metrology tools such as electronictesters and imaging tools, e.g., microscopes.

The materials and process development stage 104 may evaluate hundreds ofmaterials (i.e., a magnitude smaller than the primary stage) and mayfocus on the processes used to deposit or develop those materials.Promising materials and processes are again selected, and advanced tothe tertiary screen or process integration stage 106, where tens ofmaterials and/or processes and combinations are evaluated. The tertiaryscreen or process integration stage 106 may focus on integrating theselected processes and materials with other processes and materials.

The most promising materials and processes from the tertiary screen areadvanced to device qualification stage 108. In device qualification, thematerials and processes selected are evaluated for high volumemanufacturing, which normally is conducted on full wafers withinproduction tools, but need not be conducted in such a manner. Theresults are evaluated to determine the efficacy of the selectedmaterials and processes. If successful, the use of the screenedmaterials and processes can proceed to the manufacturing stage 110.

The schematic diagram 100 is an example of various techniques that maybe used to evaluate and select materials and processes for thedevelopment of semiconductor devices. The descriptions of primary,secondary, etc. screening and the various stages 102-110 are arbitraryand the stages may overlap, occur out of sequence, be described and beperformed in many other ways.

FIG. 1B illustrates a substrate 120 having multiple regions forcombinatorial processing in accordance with various techniques describedherein. Substrate 120 includes several regions 122 on whichsemiconductor processes can be performed. For example, the regions 122a, 122 b, and 122 c may each have an electroless layer deposited onthem. The region 122 a may use a first chemical formulation, the region122 b may use a second chemical formulation, and the region 122 c mayuse a third chemical formulation. The resulting layers can be comparedto determine the relative efficacy of each of the formulations. None,one, or more of the formulations can then be selected to use withfurther combinatorial processing or larger scale processing (e.g.,manufacturing). Any process variable (e.g., time, composition,temperature) or process sequencing can be varied using combinatorialprocessing.

As discussed above, each of the regions 122 may or may not be siteisolated. Site isolation refers to a condition where the regions 122 canbe processed individually and independently without interference fromneighboring regions. For example, one or more of the regions 122 mayinclude a sleeve having an end that forms a fluid seal with thesubstrate 120. The sleeve is configured to contain processing fluids(e.g., chemicals), and is made from a material (e.g.polytetrafluoroethylene (PTFE)) that does not react with the processingchemicals used. The chemicals do not leak out of the region into whichthey were dispensed, and each region 122 can be processed and evaluatedindividually.

Each of the regions 122 may be processed using a cell of a combinatorialprocessing tool, as described in FIG. 2. The tool is calibrated so thatprocessing in each of the regions 122 is consistent and comparable.Using techniques described herein, pressure within the combinatorialprocessing tool may be monitored and the pressure supplied to thechemical supply vessel or bottle can be adjusted so that the flow ratein the flow cells stays consistent and calibrated. With thesetechniques, processed regions across one or multiple substrates may showreliable results that can be compared and characterized when performingcombinatorial processing. For example, some of the implementationsdescribed herein can help provide consistent fluid delivery acrossmultiple regions of a substrate. These embodiments can improvecombinatorial processing by improving repeatability and comparability ofcertain processing techniques.

Combinatorial Processing Tool

FIG. 2 illustrates a combinatorial processing tool 200 in which one ormore implementations of various technologies described herein may beincorporated and used. Although various implementations described hereinare with reference to the combinatorial processing tool 200, it shouldbe understood that some implementations may use other types ofcombinatorial processing tool, such as a combinatorial processing toolwith an open deck or any other type of combinatorial processing toolthat uses stirring.

The combinatorial processing tool 200 may include a reactor block 206having a plurality of reactor cells 208. The reactor block 206 isconfigured to mate with a stage or chuck 204, which is configured tosecure a substrate 215. The combinatorial processing tool 200 may alsoinclude a floating reactor sleeve or wall 210, which may be configuredto float or be dynamically positionable in each reactor cell 208.

FIG. 3 illustrates a schematic diagram of a combinatorial processingtool 300 according to implementations of one or more technologiesdescribed herein. The combinatorial processing tool 300 illustrated inFIG. 3 may be a wet processing tool and may be a portion of a largercombinatorial processing tool. Portions of the combinatorial processingtool 300 may be replicated several times within a larger combinatorialprocessing tool such that a larger number of variations in substrateprocessing conditions may be achieved.

The combinatorial processing tool 300 illustrated in FIG. 3 may bedivided into three parts. A chemical supply portion 302 may supplychemicals to a chemical mixing portion 304 and a site isolated reactorportion 306. The chemical mixing portion 304 may be used for mixingvarious chemicals, e.g., liquid chemicals, into solutions which may beapplied to various locations on a substrate in the reactor portion 306.In one implementation, the chemical mixing portion 304 may be removedfrom the combinatorial processing tool 300. The reactor portion 306 maycontain a site isolated reactor and may apply the solutions to thesubstrate or portions of the substrate and may subject the substrate orportions thereof to various processing conditions.

The supply portion 302 of the combinatorial processing tool 300 mayinclude a supply vessel 310 containing a liquid chemical. The chemicalmay be applied to the substrate or may be mixed with another chemical toform a solution which is to be applied to the substrate. As illustratedin FIG. 3, a pressure source Ps1 and a pressure regulator Pn1 may becoupled to the supply vessel 310 via a pressure supply line 312.Together the pressure source Ps1 and the pressure regulator Pn1 mayprovide a pressurized gas, such as Nitrogen, at a regulated pressure tothe supply vessel 310 via the pressure supply line 312. In this manner,the pressurized gas may be used to push the liquid chemical out of thesupply vessel 310 and into a supply line 314 connecting the supplyvessel 310 to a supply manifold Vd1.

A shutoff valve Sv, a pressure indicator Pd, and a dispenser, such assyringe Sg, may be coupled to the supply line 314. The syringe Sg mayhave a barrel to store the liquid chemical and a plunger to pull or pushthe liquid chemical into or out of its barrel. The pressure indicator Pdmay be used to monitor the pressure within the supply line 314, and theshutoff valve Sv may be used to provide or deny access between thesupply line 314 and the supply vessel 310.

The supply manifold Vd1 may contain a plurality of two-way and/or multiway valves connecting the supply vessel 310 to a plurality of mixingcells/vessels within the combinatorial processing tool 300. Furthermore,in lieu of a single supply vessel 310, a plurality of supply vesselscontaining various chemicals may be coupled to the supply manifold Vd1such that the supply manifold Vd1 may supply various chemicals tomultiple mixing portions or multiple site isolated reactor portions ofthe combinatorial processing tool 300. Additionally, in lieu of a singlesupply manifold Vd1, a plurality of supply manifolds Vd1 may be presentin the combinatorial processing tool 300. Together the plurality ofsupply vessels, valves, and supply manifolds may enable the supply ofvarious chemicals and chemical mixtures to the mixing portion 304 andthe site isolated reactor portion 306 of the combinatorial processingtool 300.

The supply line 314 may couple the supply vessel 310 to the supplymanifold Vd1 via one or more valves within the supply manifold Vd1. Inthis manner, the supply manifold Vd1 may control the flow of chemicalsfrom the supply vessel 310 to the mixing portion 304 or the reactorportion 306 of the combinatorial processing tool 300.

The output of the valve in the supply manifold Vd1 may be coupled via adispense path 318 to a valve Vp2. Each valve in the supply manifold Vd1may be coupled to a different dispense path 318. The dispense path 318may include one of multiple lines that may connect to the valve Vp2.Each dispense path 318 may be of a different length or made up ofdifferent properties which may result in different resistances in eachpath. The valve Vp2 may be a multi-way valve which controls the flow offluids/chemicals from the supply manifold Vd1 into either the mixingportion 304, site-isolated reactor portion 306, or both. In oneimplementation, the combinatorial processing tool 300 may not have thesupply manifold Vd1 coupled to the supply vessel 310; instead, thesupply vessel 310 may be coupled to directly to the dispense path 318.

The controller 316 may include a central processing unit (CPU), a systemmemory and a system bus that couples various system components includingthe system memory to the CPU. The system memory may include a read onlymemory (ROM) and a random access memory (RAM). A basic input/outputsystem (BIOS) containing the basic routines that help transferinformation between elements within the controller 316, such as duringstart-up, may be stored in the ROM. A number of program modules may bestored on the ROM or RAM, including an operating system and one or moreapplication programs, which may carry out the tasks described later inFIGS. 4-6. The controller 316 may be configured to send and receivesignals from other devices to perform some or all of the tasks describedherein.

The controller 316 may be coupled to certain components in the supplyportion 302 to control the calibration process, such as the pressureregulator Pn1, pressure indicator Pd, shutoff valve Sv, and each of thevalves in the supply manifold Vd1. The controller 316 may provide thepressure regulator Pn1 a predetermined pressure to supply the supplyvessel 310 based on an input of a user. The pressure indicator Pd mayindicate to the controller 216 the pressure value of the supply line314. The controller 316 may also control the opening and closing of theeach valve, including the shutoff valve Sv and the valves within thesupply manifold Vd1.

The controller 316 may also be coupled to a motor attached to theplunger of the syringe Sg. The controller 316 may send a command to themotor to push or pull the plunger such that the fluid may be provided toor drawn from the supply line 314. In one implementation, the motor maybe a step motor such that the motor turns in equal, discrete steps, andthe controller 316 may control the direction and the number of steps inwhich the motor may take.

The mixing portion 304 of the combinatorial processing tool 200 may beconfigured to facilitate thorough solution mixing of chemicals providedby supply portions. In order to form a solution, a plurality ofchemicals may flow from the supply portion 302, e.g., the supply vessel310, into different mixing vessels in the mixing portion 304. The mixingvessel 320 may then mix the chemicals to form solutions. The mixingportion 304 may also provide accurate temperature and pH control of asolution being mixed in the mixing portion 304.

A pressure source Ps2 and a pressure regulator Pn2 may be coupled to themixing vessel 320 via a valve Vr and a supply line 322. Together thepressure source Ps2 and the pressure regulator Pn2 may provide apressurized gas, e.g., Nitrogen, at a regulated pressure to the mixingvessel 320 via the valve Vr and the supply line 322. An outlet of thevalve Vr may be coupled to another valve Vg to vent pressure within thesupply line 322. The pressure in the supply line 322 may be measured bya pressure transducer Pg.

The pressurized gas provided by the pressure source Ps2 and the pressureregulator Pn2 may push the mixed chemicals in the mixing vessel 320through a line 324 and into the site-isolated reactor portion 206 of thecombinatorial processing tool 300. The mixed chemicals may flow througha valve Vf1 and into a flow cell 326. The flow cell 326 may be oneportion of a site isolated reactor, and may be used to apply the mixedchemicals to a portion or portions of a substrate under processing inthe site-isolated reactor portion 306 of the combinatorial processingtool 300. The flow cell 326 may be one of a series of parallel cellsforming site-isolated reactors which may be configured to effectsite-isolated processing on proximate regions on the substrate. Each ofthe flow cells may be configured to effect site isolated processing, forexample, by flowing fluids (e.g., mixed chemicals) onto proximateregions on the substrate. Chemicals may be provided to the flow cell 326and, consequently, to a substrate via the supply manifold Vd1.

In some implementations, different numbers of flow cells 326 may beoperating simultaneously. For example, during one operation only oneflow cell may be open, while during another, eight may be open. Thevariability of the number of flow cells in operation changes the flowvolume demands. Using the techniques described herein, the pressure inthe supply vessel 310 can be adjusted during changes in the number offlow cells operating within the combinatorial processing tool 300 tomaintain fluid flow rate calibration and consistent processing acrossmultiple regions.

Calibration of a Chemical Dispense System

As described above, the supply portion 302 of the combinatorialprocessing tool 300 may supply fluids (e.g., liquid chemicals) to themixing portion 304 and the reactor portion 306 of the combinatorialprocessing tool 200. For example, the supply vessel 310 may supply afluid via the supply line 314, the supply manifold Vd1, the dispensepath 318 to the mixing portion 304 and the reactor portion 306 of thecombinatorial processing tool 300.

In combinatorial processing tools, in order to reliably and consistentlyprocess multiple regions of a substrate, it may be desirable to controlthe flow rate of the chemical liquid in a particular dispense path 318to the mixing portion 304 and/or the reactor portion 306 of thecombinatorial processing tool. However, in some circumstances the flowrate of the fluid may be affected by the various impedances of eachdispense path. For example, if the pressure applied to the supply vessel310 by the pressure source Ps1 is constant and only a first valve in thesupply manifold Vd1 is opened to couple the supply line to a firstsingle flow cell 326 via a first dispense path 318, the flow rate out ofthe supply vessel 310 may be a first value. However, if a second valvein the supply manifold Vd1 is opened to supply fluids from the supplyvessel 310 to a second single flow cell 326 via a second dispense path318, the flow rate out of the supply vessel 310 may be a second valuedistinct from the first. For example, some flow paths may have differentlengths, may be made of different materials, may include bends, etc.that may affect the total impedance of the flow path. Additionally, ifthe pressure applied to the supply vessel 310 by the pressure source Ps1is constant, the flow rate in the supply line 314 may also change orvary based on the height of the liquid in the supply vessel 310.

Consequently, a need exists for calibrating a flow rate with respect tothe applied pressure for each dispense path 318 in the combinatorialprocessing system. Implementations described herein provide technologiesand devices for providing a specified fluid flow rate into destinationvessels (e.g., mixing vessels and/or flow cells). According to oneimplementation, the specified fluid flow rate may be obtained byproviding a specified pressure to the supply vessel containing theliquid. The pressure value required to create the specified fluid flowrate may be determined using data obtained from calibration datacorrelating the fluid flow rate and the corresponding pressure for eachdispense path 318.

FIG. 4 illustrates a method 400 for calibrating a chemical dispensesystem by creating calibration data pertaining to the fluid flow rateand its corresponding pressure for each dispense path 318 in accordancewith implementations of various techniques described herein. Method 400may be executed by the controller 316 illustrated in FIG. 3.

At step 410, the controller 316 may send a command to the motor attachedto the plunger of the syringe Sg to push the plunger completely into thebarrel of the syringe Sg such that all of the fluid contained in thebarrel may be removed.

At step 420, the controller 316 may close all of the valves in thesupply manifold Vd1.

At step 430, the controller 316 may open the shutoff valve Sv to providethe syringe Sg access to the supply vessel 310 via the supply line 314.

At step 440, the controller 316 may send a command to the motor attachedto the plunger to pull the plunger to draw the fluid from the supplyvessel 310 to the barrel of the syringe Sg. In one implementation, themotor may pull the plunger such that the barrel or cylinder of thesyringe is completely full.

At step 450, the controller 316 may close the shutoff valve Sv such thatthe supply line 314 may not have access to the supply vessel 310. Inthis manner, the fluid drawn in step 440 may be prevented from returningto the supply vessel 310. Instead, a path may be created for the fluidto flow to the supply manifold Vd1.

At step 460, the controller 316 may open a first valve of the supplymanifold Vd1 such that the fluid contained in the syringe Sg may have apath to a first destination vessel via the supply line 314, the firstvalve of the supply manifold Vd1, and the first dispense path 318. Inone implementation, the combinatorial processing tool 300 may not havethe supply manifold Vd1 coupled to the supply vessel 310; instead, thesupply vessel 310 may be coupled to directly to the dispense path 318.

At step 470, the controller 316 may send a command to the motor to pushthe plunger of the syringe Sg at a constant velocity or at an initialvelocity with a constant acceleration depending on the preference of theuser. In one implementation, the controller 316 may store into itsmemory the time in which the motor started to push the plunger and thetime in which the motor completed each motor step.

At step 480, the controller 316 may calculate the flow rate of the fluidbeing provided to the destination vessel via supply line 314 anddispense path 318. The controller 316 may use the amount of steps thatthe motor has taken while pushing the plunger, the initial time in whichthe motor started pushing the plunger, and the times in which each motorstep was taken to determine the fluid flow rate. For example, each motorstep may correspond to a known volume of fluid that has been dispensedinto the chemical dispense system. The controller 316 may then determinethe amount of time that has elapsed between each motor step. Using thevolume of the fluid dispensed and the time elapsed during a motor step,the controller 316 may determine the fluid flow rate after each motorstep. Although the controller 316 has been described to determine thefluid flow rate based on the volume dispensed and the time elapsedduring a single motor step, it should be noted that the volume of fluiddispensed and time elapsed may also be determined for other motor stepincrements such as ½, ⅔, ¾, multiple motor steps, or the like.

Referring back to step 480, the controller 316 may also record thepressure value from the pressure indicator Pd at the time in which eachmotor step was completed.

At step 490, the controller 316 may make a correlation between eachcalculated flow rate and its corresponding pressure. For example, thecorrelation can be used to determine a flow rate based on a measuredpressure (see FIG. 5). In one implementation, if the controller 316 senta command to the motor to push the plunger at a constant velocity, theflow rate and pressure correlations may remain relatively the same foreach motor step. If the controller 316 sent a command to the motor topush the plunger at an initial velocity with a constant acceleration,the flow rate and pressure value correlation may change for each motorstep, and thus provide a wide range of calibration data pertaining tothe various pressures and corresponding flow rates of a dispense path.The controller 316 may store the correlation into a memory ascalibration data for the first destination path 318. In oneimplementation, steps 410-490 may be repeated for each destination path318 to create specific calibration data pertaining to each destinationpath 318. The steps 410-490 may also be repeated at different velocitiesfor each dispense path 318.

Providing a Specific Volume to a Destination Vessel

FIG. 5 illustrates a method 500 for providing a specific volume of afluid to a destination vessel in a chemical dispense system inaccordance with implementations of various techniques described herein.Method 500 may be executed by the controller 316 illustrated in FIG. 3.In performing method 500, the controller 316 may require calibrationdata pertaining to the fluid flow rate and pressure correlations foreach dispense path of the chemical dispense system as recorded by method400. For example, the method 500 can be used in implementingcombinatorial processing to deliver fluids to a reactor in a consistent,repeatable manner (e.g., accurate flow rate, volume, and pressure).

At step 510, the controller 316 may receive a volume of a fluid, atarget pressure, and a dispense path 318 from a user.

At step 520, the controller 316 may use the calibration data obtainedfrom method 400 to determine the fluid flow rate that corresponds to thetarget pressure value and the specific dispense path 318 received fromthe user.

At step 530, the controller 316 may calculate the time required toprovide the predetermined volume of the fluid to a destination vesselvia the specified dispense path 318 based on the corresponding flowrate. For example, the calibration data may indicate that dispense path‘N’ may have a 3 milliliter per second fluid flow rate at the targetpressure specified by the user. If the volume specified by the user was6 milliliters, the controller 316 may determine that 2 seconds may berequired to provide the predetermined volume of the fluid to thedestination vessel via the specified dispense path 318.

At step 540, the controller 316 may close all of the valves at thesupply manifold Vd1 and open the shutoff valve Sv.

At step 550, the controller 316 may send a command to the pressureregulator Pn1 to regulate the pressure from the pressure source Ps1 suchthat the target pressure may be applied to the supply line 314.

At step 560, the controller 316 may open one valve of the supplymanifold Vd1 coupled to the dispense path 318 specified by the user atstep 510. In one implementation, the controller 316 may start a timer atthe instant the valve is opened to measure the time in which the fluidmay be flowing into its destination vessel.

At step 570, the controller 316 may close the valve of the supplymanifold Vd1 coupled to the specified dispense path 318 after thecalculated time to provide the predetermined volume of the fluid to adestination vessel has expired. In one implementation, the controller316 may compare the calculated time to the timer initiated when thevalve may have been opened. When the calculated time equals the timeindicated on the timer, the controller 216 may close the valve at thesupply manifold Vd1.

It should be noted that correction factors may be built into each methoddescribed in FIGS. 4-6 to account for certain sources of errors. In oneimplementation, when the syringe is accelerated, the pressure versusflow rate curve shifts. The correction factor may be extracted, in asimple method by obtaining pressure versus flow rate curves fordifferent accelerations. The pressure versus flow rate curves may beused to extrapolate to the case of zero acceleration to obtain the trueflow rate versus pressure curve.

Although FIG. 5 illustrates a method 500 for providing a specific volumeof a fluid to a destination vessel in a chemical dispense system, itshould be noted that the method 500 may also be used to provide adestination vessel a fluid at a specified flow rate. In oneimplementation, the controller 316 may receive a request to provide adestination vessel a fluid at a specified flow rate via a specifieddispense path.

The controller 316 may then use the calibration data obtained frommethod 400 to determine the pressure value that corresponds to thespecified flow rate of the fluid and the specific dispense path 318received from the user (step 520).

After determining the pressure value that corresponds to the specifiedflow rate of the fluid and the specific dispense path 318 received fromthe user, the controller 316 may then conduct steps 540-570 in the samemanner as described above. However, at step 570, the controller 316 mayclose the valve of the supply manifold Vd1 coupled to the specifieddispense path 318 after a specified amount of time has elapsed asopposed to a calculated amount of time to fill a destination vessel witha specified volume.

Controlling Pressure with a Dispenser

FIG. 6 illustrates a method 600 for controlling the pressure of thefluid in the supply line 314 with the syringe Sg in a chemical dispensesystem in accordance with implementations of various techniquesdescribed herein. Method 600 may be executed by the controller 316illustrated in FIG. 3. The method 600 in one embodiment is a feedbacksystem that measures a pressure in a flow line and adjusts the flow rate(by adjusting, e.g., the velocity of the syringe plunger) to achieve adesired pressure of fluid delivery into a flow cell.

At step 610, the controller 316 may receive a target pressure from auser such that a fluid may be delivered into the supply line 314. In oneimplementation, the controller 316 may open one valve of the supplymanifold Vd1 and close the shutoff valve Sv such that the syringe Sg maybe coupled to a destination vessel via a destination path 318.

At step 620, the controller 316 may send a command to the motor attachedto the plunger of the syringe Sg containing the fluid to push theplunger at an initial velocity.

At step 630, the controller 316 may receive a pressure value from thepressure indicator Pd.

At step 640, the controller 316 may compare the received pressure valuewith the target pressure value received by the controller at step 610.

At step 650, the controller 316 may adjust the velocity at which thecontroller 216 is pushing the plunger of the syringe Sg such that thepressure on the supply line changes to match the target pressure. In oneimplementation, if the measured pressure value is less than the targetpressure, the controller 316 may send a signal to the motor coupled tothe plunger of the syringe Sg to increase the velocity in which themotor is pushing the plunger. Conversely, if the measured pressure valueis greater than the target pressure, the controller 316 may send asignal to the motor coupled to the plunger of the syringe Sg to decreasethe velocity in which the motor is pushing the plunger.

At step 660, the controller 316 may maintain the velocity at which itpushes the plunger of the syringe Sg after determining the velocity thatcorresponds to the target pressure.

While the foregoing is directed to implementations of varioustechnologies described herein, other and further implementations may bedevised without departing from the basic scope thereof, which may bedetermined by the claims that follow. Although the subject matter hasbeen described in language specific to structural features and/ormethodological acts, it is to be understood that the subject matterdefined in the appended claims is not necessarily limited to thespecific features or acts described above. Rather, the specific featuresand acts described above are disclosed as example forms of implementingthe claims.

What is claimed is:
 1. A method for operating a chemical dispense systemhaving a plurality of dispense paths, the method comprising: causingfluid to flow through each of the plurality of dispense paths;calculating a flow rate of the fluid through each of the plurality ofdispense paths; monitoring a pressure within each of the plurality ofdispense paths during the flow of fluid therethrough; for each of theplurality of dispense paths, generating and storing a correlationbetween the respective calculated flow rate and the respective pressurewithin during the flow of fluid therethrough; receiving a selection of afirst of the plurality of dispense paths and a selection of a targetpressure; determining a target flow rate for the selected dispense pathbased on the target pressure and the correlation between the calculatedflow rate and the pressure for the first selected dispense path; andcausing fluid to flow through the first selected dispense path at thetarget flow rate.
 2. The method of claim 1, further comprising:receiving a selection of a target fluid volume; calculating a timerequired to provide the target fluid volume based on the target flowrate; and initiating and ceasing the flow of fluid through the firstselected dispense path such that the fluid flows through the firstselected dispense path for the calculated time.
 3. The method of claim2, further comprising: receiving a selection of a second of theplurality of dispense paths and a selection of a second target pressure;and determining a second target flow rate for the second selecteddispense path based on the second target pressure and the correlationbetween the calculated flow rate and the pressure for the secondselected dispense path; and causing fluid to flow through the secondselected dispense path at the target flow rate.
 4. The method of claim3, further comprising combinatorially processing first and secondregions of a substrate with the fluid flowing through the respectivefirst and second selected dispense paths.
 5. The method of claim 4,wherein the combinatorially processing the first and second regions ofthe substrate comprises varying a processing condition between theprocessing of the first region of the substrate and the second region ofthe substrate.
 6. The method of claim 5, wherein the varied processingcondition is the pressure at which the respective fluid is delivered. 7.The method of claim 1, wherein the monitoring of the pressure for all ofthe plurality of dispense paths is performed with a single pressureindicator.
 8. The method of claim 7, wherein the pressure indicator is apressure transducer coupled to a fluid line in fluid communication withthe plurality of dispense paths.
 9. The method of claim 1, wherein thegenerating and the storing of the correlations is performed with aprocessing device.
 10. A substrate processing tool comprising: a supplyline to provide fluid to a plurality of destination vessels through aplurality of dispense paths; an array of valves coupled between thesupply line and the plurality of dispense paths; a dispenser in fluidcommunication with the supply line; a pressure transducer coupled to thesupply line and configured to measure pressure within the supply line;and a controller coupled to the array of valves, the dispenser, and thepressure transducer, the controller being configured to: cause fluid toflow through each of the plurality of dispense paths; calculate a flowrate of the fluid through each of the plurality of dispense paths;monitor a pressure within each of the plurality of dispense paths duringthe flow of fluid therethrough; for each of the plurality of dispensepaths, generate and store a correlation between the respectivecalculated flow rate and the respective pressure within during the flowof fluid therethrough; receive a selection of a first of the pluralityof dispense paths and a selection of a target pressure; determine atarget flow rate for the selected dispense path based on the targetpressure and the correlation between the calculated flow rate and thepressure for the first selected dispense path; and cause fluid to flowthrough the first selected dispense path at the target flow rate. 11.The substrate processing tool of claim 10, wherein the controller isfurther configured to: receive a selection of a target fluid volume;calculate a time required to provide the target fluid volume based onthe target flow rate; and initiate and cease the flow of fluid throughthe first selected dispense path such that the fluid flows through thefirst selected dispense path for the calculated time.
 12. The substrateprocessing tool of claim 11, wherein the controller is furtherconfigured to: receive a selection of a second of the plurality ofdispense paths and a selection of a second target pressure; anddetermine a second target flow rate for the second selected dispensepath based on the second target pressure and the correlation between thecalculated flow rate and the pressure for the second selected dispensepath; and cause fluid to flow through the second selected dispense pathat the target flow rate.
 13. The substrate processing tool of claim 12,wherein the processor is further configured to combinatorially processfirst and second regions of a substrate with the fluid flowing throughthe respective first and second selected dispense paths.
 14. Thesubstrate processing tool of claim 13, wherein the combinatoriallyprocessing the first and second regions of the substrate comprisesvarying a processing condition between the processing of the firstregion of the substrate and the second region of the substrate.
 15. Thesubstrate processing tool of claim 14, wherein the varied processingcondition is the pressure at which the respective fluid is delivered.